We're all animals for sure. I wouldn't stop at animals though. What makes sense is that everyone and everything is the universe.

I wouldn't equate death with the end of existence. You know yourself that you exist and you will always exist at this time and moment, even after death in the future. I don't think there is an afterlife either, but it's ok, because organic life dies all the time and life still continues to exist.

We can observe and explore the universe as long as we are conscious and it's difficult to let go of it. I agree that we don't know much and we probably never will. Our minds are amazing already, just think how it is capable to assemble a reality in your head from your senses. But I don't believe in myself making any discoveries. Our minds are very limited. We cannot even imagine a room with more than three dimensions. On top of that, the minds of many on here including mine seems to be preoccupied with worries, anxiety and depression.